Find the differential equations corresponding to `v=(A)/(r )+B`.

Explanation

`v=(A)/(r )+B` …………..`(1)`
`implies (dv)/(dr)=-(A)/(r^(2))implies-A=r^(2)*(dv)/(dr)`
`implies0=[r^(2)*(d^(2)v)/(dr^(2))+(dv)/(dr)*2r]`
`implies r*(d^(2)v)/(dr^(2))+2(dv)/(dr)=0`.
which is the required differential equation.